AdventOfCode2022/01/main.rs

#![allow(dead_code)]
use std::fs::File;
use std::io;
use std::io::BufRead;
use std::path::Path;
use std::time::Instant;

fn main() {
    let now = Instant::now();
    part_one();
    let part_one_duration = now.elapsed();
    part_two();
    let part_two_duration = now.elapsed();
    println!(
        "p1: {}ms, p2: {}ms",
        part_one_duration.as_millis(),
        (part_two_duration - part_one_duration).as_millis()
    );
}

fn read_lines<P>(filename: P) -> io::Result<io::Lines<io::BufReader<File>>>
where
    P: AsRef<Path>,
{
    // note that this discards a final newline
    let file = File::open(filename)?;
    Ok(io::BufReader::new(file).lines())
}

fn part_one() {
    if let Ok(lines) = read_lines("./inputs/input") {
        let mut biggest = 0;
        let mut accumulator = 0;
        for line in lines {
            if let Ok(calories) = line {
                if calories != "" {
                    accumulator += calories.parse::<u32>().unwrap();
                } else {
                    if accumulator > biggest {
                        biggest = accumulator
                    }
                    accumulator = 0;
                }
            }
        }
        // catching final elf
        if accumulator > biggest {
            biggest = accumulator
        }
        println!("{}", biggest);
    }
}

fn part_two() {
    if let Ok(lines) = read_lines("./inputs/input") {
        let mut elves = Vec::new();
        let mut accumulator = 0;
        for line in lines {
            if let Ok(calories) = line {
                if calories != "" {
                    accumulator += calories.parse::<u32>().unwrap();
                } else {
                    elves.push(accumulator);
                    accumulator = 0;
                }
            }
        }
        // catching final elf
        elves.push(accumulator);
        elves.sort_unstable();
        println!(
            "{}",
            elves.pop().unwrap() + elves.pop().unwrap() + elves.pop().unwrap()
        );
    }
}